The biggest goal, at least a few years ago, was to have a Ruby that is substantially implemented in Ruby, as opposed to being a hundred thousand lines of C under the hood. Paradoxically, this can result in speedups, since it's easier to optimize expressive, well-written code. Avi Bryant gave a talk at RailsConf a few years ago about how Smalltalk contains all the "features" of Ruby that are usually blamed for its performance woes, but still managed to be pretty fast. It's not the language features that keeps Ruby slow; it's the opaque implementation.
I think they are on the right track. Given that this is a 3 year old project, I don't think we can compare it to smalltalk implementation with years of development. I wonder how well it would compare to something like pypy and other similar projects.
Can't blame them, even a year or two ago Ruby and RoR were much inferior to today. And wait till RoR3 hits the shelves full steam. Granted I hope ActiveRecord3 will include everything by default like DataMapper does but whatever...
Ruby is still in infancy stages, Python is quite old. Hell Python was the inspiration for Ruby.
I mean look at what is happening in the Javascript space. If Ruby and JRuby implementations get really f-ing fast, we will get some major backings. The problem is that instead of improving Ruby, Twitter decided to ditch it. Maybe they really didn't have the people Google has when it comes to language builders. Since google app engine runs python it is in direct google interest to make it fast. Once it starts running ruby, vuala! So don't worry, they'll get to it.
Python was released in 1991; Ruby was released in 1995. If Ruby is significantly lagging behind Python at this point, it seems unlikely to make up the difference in the future.
